/*
*
* libnet 1.1
* Build a DNSv4 packet
* To view: /usr/sbin/tcpdump -vvvvven -s 0 port 53
*
* Copyright (c) 2003 Frédéric Raynal <pappy@security-labs.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#if (HAVE_CONFIG_H)
#include "../include/config.h"
#endif
#include "./libnet_test.h"
#ifdef __WIN32__
#include "../include/win32/getopt.h"
#endif
void
usage(char *prog)
{
fprintf(stderr, "Usage: %s -d dst_ip -q query_host [-s src_ip] [-t]\n", prog);
exit(1);
}
int
main(int argc, char *argv[])
{
char c;
u_long src_ip = 0, dst_ip = 0;
u_short type = LIBNET_UDP_DNSV4_H;
libnet_t *l;
libnet_ptag_t ip;
libnet_ptag_t ptag4; /* TCP or UDP ptag */
libnet_ptag_t dns;
char errbuf[LIBNET_ERRBUF_SIZE];
char *query = NULL;
char payload[1024];
u_short payload_s;
printf("libnet 1.1 packet shaping: DNSv4[raw]\n");
/*
* Initialize the library. Root priviledges are required.
*/
l = libnet_init(
LIBNET_RAW4, /* injection type */
NULL, /* network interface */
errbuf); /* error buffer */
if (!l)
{
fprintf(stderr, "libnet_init: %s", errbuf);
exit(EXIT_FAILURE);
}
/*
* parse options
*/
while ((c = getopt(argc, argv, "d:s:q:t")) != EOF)
{
switch (c)
{
case 'd':
if ((dst_ip = libnet_name2addr4(l, optarg, LIBNET_RESOLVE)) == -1)
{
fprintf(stderr, "Bad destination IP address: %s\n", optarg);
exit(EXIT_FAILURE);
}
break;
case 's':
if ((src_ip = libnet_name2addr4(l, optarg, LIBNET_RESOLVE)) == -1)
{
fprintf(stderr, "Bad source IP address: %s\n", optarg);
exit(EXIT_FAILURE);
}
break;
case 'q':
query = optarg;
break;
case 't':
type = LIBNET_TCP_DNSV4_H;
break;
default:
exit(EXIT_FAILURE);
}
}
if (!src_ip)
{
src_ip = libnet_get_ipaddr4(l);
}
if (!dst_ip || !query)
{
usage(argv[0]);
exit(EXIT_FAILURE);
}
/*
* build dns payload
*/
payload_s = snprintf(payload, sizeof payload, "%c%s%c%c%c%c%c",
(char)(strlen(query)&0xff), query, 0x00, 0x00, 0x01, 0x00, 0x01);
/*
* build packet
*/
dns = libnet_build_dnsv4(
type, /* TCP or UDP */
0x7777, /* id */
0x0100, /* request */
1, /* num_q */
0, /* num_anws_rr */
0, /* num_auth_rr */
0, /* num_addi_rr */
payload,
payload_s,
l,
0
);
if (dns == -1)
{
fprintf(stderr, "Can't build DNS packet: %s\n", libnet_geterror(l));
goto bad;
}
if (type == LIBNET_TCP_DNSV4_H) /* TCP DNS */
{
ptag4 = libnet_build_tcp(
0x6666, /* source port */
53, /* destination port */
0x01010101, /* sequence number */
0x02020202, /* acknowledgement num */
TH_PUSH|TH_ACK, /* control flags */
32767, /* window size */
0, /* checksum */
0, /* urgent pointer */
LIBNET_TCP_H + LIBNET_TCP_DNSV4_H + payload_s, /* TCP packet size */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (ptag4 == -1)
{
fprintf(stderr, "Can't build UDP header: %s\n", libnet_geterror(l));
goto bad;
}
ip = libnet_build_ipv4(
LIBNET_IPV4_H + LIBNET_TCP_H + type + payload_s,/* length */
0, /* TOS */
242, /* IP ID */
0, /* IP Frag */
64, /* TTL */
IPPROTO_TCP, /* protocol */
0, /* checksum */
src_ip, /* source IP */
dst_ip, /* destination IP */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (ip == -1)
{
fprintf(stderr, "Can't build IP header: %s\n", libnet_geterror(l));
exit(EXIT_FAILURE);
}
}
else /* UDP DNS */
{
ptag4 = libnet_build_udp(
0x6666, /* source port */
53, /* destination port */
LIBNET_UDP_H + LIBNET_UDP_DNSV4_H + payload_s, /* packet length */
0, /* checksum */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (ptag4 == -1)
{
fprintf(stderr, "Can't build UDP header: %s\n", libnet_geterror(l));
goto bad;
}
ip = libnet_build_ipv4(
LIBNET_IPV4_H + LIBNET_UDP_H + type + payload_s,/* length */
0, /* TOS */
242, /* IP ID */
0, /* IP Frag */
64, /* TTL */
IPPROTO_UDP, /* protocol */
0, /* checksum */
src_ip, /* source IP */
dst_ip, /* destination IP */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (ip == -1)
{
fprintf(stderr, "Can't build IP header: %s\n", libnet_geterror(l));
exit(EXIT_FAILURE);
}
}
/*
* write to the wire
*/
c = libnet_write(l);
if (c == -1)
{
fprintf(stderr, "Write error: %s\n", libnet_geterror(l));
goto bad;
}
else
{
fprintf(stderr, "Wrote %d byte DNS packet; check the wire.\n", c);
}
libnet_destroy(l);
return (EXIT_SUCCESS);
bad:
libnet_destroy(l);
return (EXIT_FAILURE);
}